Elgin Mainspring for Grades 643, 654, 678 & 1423, No. 6750 - Alloy

Elgin Mainspring for 11½ ligne movements, Factory No. 6750, automatic with brake, alloy, new in envelope. The 11½ ligne movements are AS 1361 ébauche based and include Grades 643, 654, 678, 1423 and perhaps others, so this mainspring will fit movements other than just the specified Elgin. Not a mainspring I run across very often. See images for further details. I specialize in hard to find watch parts and all watch parts are unconditionally guaranteed. Images do a pretty good job of representing the item